1. Field of the Invention
The present invention relates to an image processing device, an image processing method, and an image processing program.
2. Description of Related Art
In laboratories, manufacturing sites, and the like, there have been employed high-speed image-pickup devices capable of picking up images of subjects at higher frame rates, in order to analyze movements of various types of subjects (works, devices, and the like). When an image of a subject is picked up by a camera, a plurality of pieces of image data corresponding to a plurality of images are successively acquired, and the acquired plurality of pieces of image data are stored as moving-image data in a storage unit. Based on the image data stored in the storage unit, images of a plurality of frames are displayed as a moving image of the subject, on a display unit such as a liquid crystal display panel. Using such a moving image, the movements of the subject are analyzed.
During image pickup, it is necessary to adjust image-pickup conditions including a shutter speed. A user adjusts the image-pickup conditions by checking a moving image being displayed on a display unit. In cases of higher frame rates for image pickup, it is hard to display captured image data at the same frame rate as that of image pickup. This causes the captured image data to be displayed at a lower frame rate than that of image pickup.
Japanese Unexamined Patent Publication No. 2009-100326 describes a high-speed image pickup device which, after completion of high-speed image recording for a predetermined number of frame images at the time of picking up an image of a subject, slowly reproduces the recorded frame images at a lower frame rate than that of image pickup. After the completion of the slow reproduction of the frame images, high-speed image recording is started, again. Thereafter, similarly, high-speed image recording and slow reproduction are alternately repeated.
For example, when a work being transferred by a belt conveyer is a subject, there is a time interval within which the subject exists in the area to be subjected to image pickup by a camera (hereinafter, referred to as “image-pickup area”), but there is also a time interval within which the subject does not exist therein.
With the high-speed image pickup device in Japanese Unexamined Patent Publication No. 2009-100326, high-speed image recording and slow reproduction of frame images are alternately repeated at constant time intervals. This enables accurately observing movements of the subject. However, when a work on a belt conveyer is a subject as described above, frame images picked up within the time interval within which the subject exists in the image-pickup area may not be recorded, but frame images picked up within the time interval within which the subject does not exist in the image-pickup area may be recorded. This makes it impossible to observe a moving image of the subject.